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1997 Chevrolet Lumina 3.4L MIL Lamp on
Posted to GM Driveability on 5/13/2002 19 Replies

Need a little help with this car. It keep's setting a code po420,we have replaced both o2 sensor map sensor and catalytic converter. When the code set's the speed is anywhere between 40 and 68 mph. We ahve checked fuel pressure,vacuum leak's but everything che...

19 Replies Received (View Replies)

 
Message Closed

car Vehicle Data

1997 Chevrolet Lumina

VIN [No VIN Available]
Engine3.4 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI / SEFI
EmissionsOBD-II Compliant
SymptomsMIL Lamp On
OccursIntermittently

Trouble Codes

P0420Catalyst Efficiency Below Threshold (Bank 1)
Message Closed

car Vehicle Data

1997 Chevrolet Lumina

VIN [No VIN Available]
Engine3.4 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI / SEFI
EmissionsOBD-II Compliant
SymptomsMIL Lamp On
OccursIntermittently

Trouble Codes

P0420Catalyst Efficiency Below Threshold (Bank 1)